| 摘要 |
An absolute type linear encoder includes: a scale including a plurality of tracks including a high-order and low-order tracks; and a detection head configured to detect a relative position to the scale; and a processing circuit configured to obtain the number of cycles of the low-order track by using a correction value obtained per correction pitch, the width of which is wider than the detection pitch, based on an error between tracks produced by a difference between the position of the high-order track to the detection head and the position of the low-order track thereto, output values of the high-order track and the low-order track, and a cyclic ratio of the low-order track to the high-order track, and obtain the position of the detection head to the scale based on the number of the cycles and the output value of the low-order track. |
